Why convert MKV to MP3?

OBS recordings come out in MKV — extract just the audio in MP3 to listen, edit, or transcribe the class/livestream.

What if I need the text of this audio?

After converting, you can transcribe the file with AI on VoxScriber: 30 free minutes per month, with automatic punctuation and speaker identification. Ideal for WhatsApp audios, meetings, and interviews.

Is the MKV to MP3 converter really free?

Yes, free and unlimited. Processing happens in YOUR browser (WebAssembly), so we have no server costs — and you don't need to create an account.

Is my file sent to any server?

No. All processing is local (FFmpeg compiled to WebAssembly running on the page). The file never leaves your device — it even works offline after the page loads.

Is there a size or quantity limit?

The limit is 500 MB per file (browser memory). There is no limit on number of uses. For larger files, VoxScriber processes on the server with upload up to 5 GB.

Does it work on mobile?

Yes — any modern browser (Chrome, Safari, Firefox, Edge) on desktop or mobile. On older phones, large files may take longer.

MKV → MP3 · Extract Audio · Free · No Upload

Convert MKV to MP3 — Extract Audio Online Free

Extract MP3 audio from MKV videos directly in your browser. Free, fast, and private: the video never leaves your device.

Drop your file here or click to select

Processed in your browser — up to 500 MB. Nothing is uploaded.

100% local processing: your file never leaves your device.

Formatos suportados: .mkv files up to 500 MB — processed locally

Resultado em segundos

100% em português do Brasil

Privacidade garantida

Sem instalação

Como funciona

Upload the MKV video

Drag and drop your .mkv video (up to 500 MB). Processing is local — the video is never sent to any server.

Audio is extracted in the browser

FFmpeg in WebAssembly separates the audio track from the video without needing to install anything.

Download the MP3

The .mp3 file is ready in seconds, lightweight and compatible with any player or editor.

Perguntas frequentes

Need the text from this audio? Transcribe with AI — 30 min free

Criar conta gratuita →

30 minutos/mês grátis. Sem cartão de crédito.

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